Due to the Duchess of Cambridge suffering from a severe form of morning sickness during her pregnancies with Prince George, Princess Charlotte and Prince Louis, it was previously thought the royal family would stop at three children.
However, the UK is abuzz with rumours that another royal baby is on the way, and while Kensington Palace has not made an official comment, recent photos of Kate have royal observers convinced that William and Kate are expecting baby number four.
When the Duke and Duchess of Cambridge dropped their eldest two children Prince George and Princess Charlotte off for their first day of school at Thomas Battersea School, royal fans spotted a certain change in Kate's appearance that they believe is a clue.
The mother-of-three had cut her hair and added lighter highlights, and according toExpress, the Duchess always changes her hairstyle in the early stages of pregnancy.
The publication suggested that Kate did this to distract from a growing baby bump.
For example, before announcing her pregnancy with Prince Louis, the 37-year-old shortened her hair, and when she was pregnant with Prince George, she cut a fringe.
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Royal fans engaged in a Twitter frenzy after seeing the photos from Princess Charlotte's first day of school.
One wrote: “New hair cut - is Kate pregnant again????? She always sports a new hairstyle when she’s pregnant.”
Another said: “When Kate’s pregnant she changes up her hair so people look at her hair and not her stomach. Is baby 4 coming?”
A third added: “Kate changed her hair again, I’m pretty sure she’s pregnant.”
According to a royal insider, Princess Charlotte also “let the cat out of the bag” about a new royal baby with the 4-year-old telling everyone at school that her“mummy is having another girl”.
“One of the teaching aides overheard Charlotte saying it and couldn’t believe her ears –Charlotte was talking very loudly, and seemed convinced that her mummy was pregnant,” the source reveals.
“It was certainly quite the bombshell to drop in her first week of school!"
Following her entrance to the event via tractor with British TV personality Mary Berry, the Duchess got in touch with her maternal side as she played with children at theBack to Nature garden launch.
Wearing a floral dress by Emilia Wickstead, the mother-of-three was seen laughing and dancing with a small baby.
A local Australian publication reported that she told the child's mother that her sonPrince Louisloves to "smell flowers in the garden."
Bookies company Ladbrokes recently shortened the odds on Kate giving birth to her fourth baby by the end of 2020 to 1/2 this week after the rumours began.
In addition, they put the chances of Prince Harry and Meghan Markle giving baby Archie a sibling in 2020 at 4/7.
Alex Apati of Ladbrokes toldExpress: “There'll be plenty for royalists to sink their teeth into next year if the latest odds are anything to go by, with a royal wedding and two babies potentially on the way.”
For more royals news, pick up a copy of this month's New Idea Royals magazine.